Retaining walls are commonly used for architectural and site development applications and such soil reinforced earthen works have now become a recognized civil engineering structure useful in the retention of hillsides, right of way embankments, and the like. The wall facing elements, which typically consist of masonry blocks, concrete blocks, concrete panels or welded wire forms, must withstand lateral pressures exerted by backfill soils. Reinforcement and stabilization of the soil backfill in mechanically stabilized earth applications is commonly provided using geosynthetic materials such as geogrids or geotextiles that are placed horizontally in the soil fill behind the wall face. The geosynthetic materials interlock with the soil and create a stable reinforced soil mass. The geosynthetic materials are connected to the wall face elements.
A preferred form of grid-like tie-back sheet material used to reinforce the soil behind a retaining wall structure, known as an integral geogrid, is commercially available from The Tensar Corporation of Alpharetta, Ga. (“Tensar”) and is made by the process disclosed in U.S. Pat. No. 4,374,798 (“the '798 patent”). Integral geogrid tie-back sheet material may be uniaxially oriented according to the '798 patent to provide grid-like sheets including a plurality of elongated, parallel, molecularly oriented strands with transversely extending bars integrally connected thereto by less oriented or unoriented junctions, the strands, bars and junctions together defining a multiplicity of elongated openings. With biaxial (i.e., 2-dimensional) stretching, the bars may be oriented into elongated strands. While integral geogrids are preferred as reinforcing materials in the construction of retaining walls, other forms of tie-back sheet materials have been used in a similar manner.
The use of full height pre-cast concrete wall panels for wall-facing elements in a retaining wall is known such as is disclosed in U.S. Pat. Nos. 5,568,998 and 5,580,191. These types of systems typically require, during construction, that the panels be placed using a crane because they are very large, perhaps 5 feet (1.5 m) by 10 feet (3.0 m) or even larger and, as a result, are quite heavy such that they cannot be readily man-handled. To avoid such problems in the use of pre-cast wall panels, other types of retaining wall structures have been developed.
As one known example, retaining walls have been formed from modular wall blocks which are typically relatively small cementitious blocks as compared to cast wall panels. The assembly of modular wall blocks usually does not require heavy equipment. Such modular wall blocks can be handled by a single person and are used to form retaining wall structures by arranging a plurality of blocks in courses superimposed on each other, much like laying of brick or the like. Each block includes a body with a front face which forms the exterior surface of the formed retaining wall. Examples of such modular wall block systems are disclosed in U.S. Pat. Nos. 5,010,707; 5,522,682; 5,568,999; 5,823,709; 5,911,539; 5,934,838; and 6,287,054.
The use of welded wire (ww) facing units in the construction of retaining walls is also well known to reinforce earthen formations. U.S. Pat. Nos. 4,856,939; 6,595,726; and 8,197,159 disclose the construction of geogrid-reinforced earthen retaining walls incorporating welded wire facing units wherein portions of the face sections of the wire facing units include kinks or hooks which serve, inter alia, to retain the ends of geogrids, the remainder of the geogrids being designed to extend rearwardly into the fill to reinforce the wall. U.S. Pat. No. 4,904,124 also discloses the use of wire “baskets” that are designed to be filled with granular or rock material to define the forward or face of the wall, the elements of which are also reinforced with grid-like reinforcing sheet material to provide stability of the soil mass.
In the case of modular wall blocks that are typically used, several companies have begun utilizing blocks in a manner to create a more aesthetic wall pattern, such as the use of multiple sized blocks to create a segmented wall pattern. While providing end customers with more aesthetic pattern choices to choose from, this has typically lead to several disadvantages including the need for additional block manufacturing molds, increased time for delivery of varying sized blocks, and increased costs for the smaller block sections. As such, improvements in the art are desired to provide a retaining wall block system that utilizes one size and shaped block that can be multi-oriented to create random wall patterns while maintaining connection with the reinforcing sheet material as known in traditional block wall systems.